Compound bow. A weapon that is different from all bows and arrows except for the crossbow.

The principle of mechanical assistance and the principle of lever are used to achieve the effect of labor-saving.

The average compound bow can save up to 70% of the effort, which is an extremely anti-heaven form. In layman's terms, an archer with a 40-pound recurve bow can easily use a 70-pound compound bow.

Li Hanyang didn't believe it, he made a compound bow by himself, and he couldn't conquer Steward Liu?

Before going down the mountain, Li Hanyang first went back to his residence, opened the bed and took out the hidden money box.

There were a few silver tickets lying in the money box.

Silver is also the currency of this world. But it is mainly circulated among ordinary people. Basically, one hundred taels of silver can be exchanged for a low-grade spirit stone. In fact, five taels of silver is enough for a family of three for a month.

Li Hanyang's cultivation resources for a month are a low-grade spirit stone, and in addition to the degree of food and clothing, there is also a balance. And the spirit stone can't make change, so it can only be changed through silver.

And when you count it, there are more than one hundred and fifty taels of silver.

"Redeem!"

As soon as the words fell, there were only more than fifty taels of silver left in his hand, and one of the silver tickets of one hundred taels disappeared.

And in his hand, there was also an inexplicable extra tool with an earthy yellow body.

Angle grinder.

I'm afraid this is a newbie package......

Because this is the only tool in the system that can be exchanged for silver taels. Named 'Invincible Angle Grinder', the introduction is: permanent uninterrupted power, permanent no need to replace the grinding wheel, can grind any substance in this world.

This introduction is very rebellious.

What is an angle grinder?

An angle grinder is a grinding wheel attached to a motor, which is mainly used to cut and polish metal.

To make a compound bow, it is simply impossible to do without modern tools. First, because the iron-smelting technology in this world is too weak, it is impossible to make extremely precise eccentric wheel kits and mechanical kits in the form of mold casting.

If he wanted to get those things out, Li Hanyang had to polish the parts by hand. But the problem is that there are no modern tools, and they are polished by hand with a small file, which is the year of the monkey.

It just so happens that you have the tools you need in the system, and you happen to be able to afford them. Of course, there are cheaper ones, which are also paid for in silver taels. For example, screwdrivers, flat screwdrivers, etc. But that kind of tool Li Hanyang can't use, and that kind of most basic tool is not of much use now.

I pressed the button of the angle grinder.

The angle grinder in the hand of 'Hum' suddenly began to vibrate, and the grinding wheel spun rapidly.

Li Hanyang took the angle grinder and found a copper basin in the house and tried it.

'Zizizi' cutting sound appeared.

A second.

The brass basin was cut open.

Li Hanyang took away the angle grinder in surprise, looked at the smooth and mirror-like cutting opening on the copper basin, and exclaimed: "This speed is too high, too precise, there are no cutting marks." What kind of grinding wheel is this, I just touched it for a second, and then I cut the copper basin. ”

Tried and tested in the house and played for a long time. Li Hanyang hurriedly took the invincible angle grinder back into the system warehouse. Carry the rest of the silver and quickly descend the mountain.

opened a room in the inn at the foot of the mountain, and Li Hanyang first drew drawings.

Better tools make good work. Li Hanyang has the habit of drawing drawings, mainly because the core 'eccentric wheel' of the compound bow is too complex and precise, and it is basically impossible to make without drawings.

"According to the principles of mechanics, the disadvantages of the recurve bow are very obvious. If you want to pull a 200-pound bow, you need to have at least 400 pounds of strength. Therefore, Steward Liu can only use a 200-pound bow, not that his strength is only 200 kilograms......"

"The force used to pull a bow apart is not much, it only needs to be equal to the tension of the bow. But pulling apart is not the same as being able to shoot an arrow. The most important thing in archery is to maintain the posture of drawing the bow and continue to draw the bow, which requires 1.7 times the force of drawing the bow. If a person's explosive power is 100 catties, then he can only use a bow and arrow of 65 catties at most. He needed 65 pounds of strength to pull the bow and arrows, but he needed 100 pounds of strength to pull the bow and arrows to the fullest, and keep that position......"

While drawing the drawings of the new compound bow, Li Hanyang couldn't help blurting out the physical principles and some data he knew.

"Eccentric wheels, oval disc structure. Because the bearing is not at the very center point, it is eccentric. After the eccentric wheel group drives the bowstring, the lever principle will be generated, and under the lever principle, a large part of the manpower will be liberated, making it easier and more labor-saving to shoot the bow and arrow. With the same amount of force, it is possible to pull a bow with a larger pound and gain a greater range. Break through the extreme tension of the bow blade. ”

On the drawing, an eccentric wheel with an elliptical gear structure drawn in a sketch appears.

At this time, Li Hanyang no longer had the youthfulness of the immature boy after the crossing, and the whole person's complexion became extremely calm.

When it comes to researching his own work, he always takes it seriously. Just like teaching in his previous life, even if no student listened to his own physics class, he still meticulously explained everything in detail.

On the drawings, the principle of the eccentric wheel kit was quickly drawn, as well as the composition drawings. Even the style of the compound bow was drawn, including the finished bow, as well as the pulley kit principle. Even the crossed bowstrings were drawn.

With the drawings in hand, Li Hanyang left the inn and came to Zhen'an County, which was sent by Lingyun. Find a blacksmith shop.

"What are you going to build?" asked the shopkeeper.

"Do you have any bow pieces here?"

"Do you want to make a bow? Yes, how many pounds of bow pieces do you want?"

"350 pounds. ”

Hiss –

The shopkeeper gasped: "More than 300 catties! My mother, who called such a heavy bow?"

Li Hanyang said lightly: "You don't care who calls him, do you have it?"

"No, no, my tallest bow is only 90 pounds. ”

Li Hanyang sighed, he understood why Steward Liu handed over this matter to the outer disciples, because it couldn't be bought outside......

Yes, if you want to save trouble, you still have to make one for him yourself.

Li Hanyang hurried to the mountains and forests again and began to choose suitable bamboo. There is no way, you can't find composite materials in this world, you can only make bamboo bows.

After cutting a few bamboos, Li Hanyang simply didn't bring them back, and sat in this bamboo forest and began to make bow pieces.

In fact, it is also very difficult to make a bow piece, and he dares to guarantee that this craft is only known to the master except himself.

Soon, Li Hanyang cut a piece of bamboo, cut off a piece of bamboo, and immediately began to test. He kept measuring with the simple vernier calipers he had just made, and then measured with two ten-pound scales.

Vernier calipers clamp the bamboo pieces and measure the thickness and length. Li Hanyang kept recording data on paper.

Then bend the bamboo pieces and tie them to a rope. A weighing stone is hung in the middle to measure the tensile force of the bamboo piece.

"Bamboo pieces with a length of 1.5 meters, a thickness of 6 mm, and a width of 5 cm. It takes 16 pounds of strength to completely pull it to the limit. ”

Li Hanyang muttered and began to convert: "Then a 350-pound bow, wouldn't it take about twenty-two pieces of bamboo to do so? After it was made, the thickness of the light had to be 13 centimeters, and it was impossible to hold it with your hands. ”

After speaking, Li Hanyang fell into deep thought.

Suddenly, an idea moved: "No. I only need the tension of the bow blade, the eccentric wheel is the core, and I don't need to make it according to the shape of a traditional recurve bow at all. Yes, I can take 22 pieces of bamboo, make two pieces of bow, make two pieces of bow. Then the two bows are fastened together with buckles, at bevel angles......"

In my mind, the shape of the strange bow and arrow gradually took shape. Obviously, a bow and arrow with two bows combined together can't be used by a normal person at all, because you don't have a place to grab it.

But this is not difficult for Li Hanyang.

"When the two bows merge together, I can add a point of support between the pieces of the bow that can't shake hands. Then create a special gripper, when shooting arrows, you don't need to grasp the bow, just pull the string with one hand, and support the special handle with the other. This will also allow you to draw the bow more fully and with more power. ”

Li Hanyang slapped his thigh excitedly: "I'm really a genius." Alas, I suddenly felt that Steward Liu was not worthy of the bow I made. ”

“......”

The plan is set, and all the data on the drawings are recorded. Li Hanyang immediately began to cut those bamboos into bamboo chips of the same size.

THE BAMBOO IS THEN SMOOTHED WITH AN ANGLE GRINDER UNTIL ALL THE THICKNESS IS THE SAME, WHICH IS 6MM.

With these bow pieces in hand, Li Hanyang bought a lot of metal materials again, and then returned to his inn. He didn't want to build it in the Lingyun Sect, in case someone else discovered his angle grinder, it would be a big trouble.

At the same time, the blacksmith shop where Li Hanyang went began to welcome disciples of the Lingyun faction.

"Boss, do you have a 200-pound bow?"

"Nope. ”

"Well, that's a good thing. What should I do, I'd rather pay out of my own pocket, but I can't buy a 200-pound bow at all. ”

The blacksmith owner muttered, "What's going on today." So many people came to ask if there was a 200-pound bow, how could this mortal make a giant bow of that level? And a madman, even a 350-pound bow? Damn. ”

“......”

Many of the outer disciples of the Lingyun Sect were blinded. Only then did they realize how serious the matter was, why was Steward Liu willing to throw out the temptation of 5 spirit stones, because it was ...... It's a hard thing to do.

Li Hanyang can think of using synthetic bamboo pieces to make a double-bow compound bow, it doesn't mean that those people can think of it. Originally, they all thought that they would spend some money to buy ready-made bow blades in the mortal world, and then come back to tie a string.

It turned out to be found. How naïve and naïve I am. You'll have to build this bow yourself.

Steward Liu would rather exchange 5 spirit stones for this 200-pound bow, he is not stupid, if the mortal world can buy it, he will spend money to do it, so it won't be so far from the past......